Viewing the Heart's Electrical System in 3-D

3D cardiac conduction system images could improve heart surgery

(RxWiki News) Scientists have long had a general understanding of the cardiac conduction system, the complex electrical system in charge of muscle contractions within the heart.

However it has not been well understood. A new x-ray technique that allows scientists to view 3-D images could provide a better understanding of abnormal heart rhythms, and why the heart is left vulnerable to scarring after a heart attack.

Jonathan Jarvis, PhD, from the University of Liverpool's Institute of Ageing and Chronic Disease, said the new anatomically detailed images could improve accuracy of future computer models of the heart.

It also could provide insight into understanding how normal and abnormal heart rhythms are generated, he said, emphasizing that the 3-D imaging could provide more thorough knowledge of the cardiac conduction system and the way it changes in heart disease.

During the pre-clinical study researchers used enhanced micro-CT imaging to view the hearts of four rats and four rabbits first treated with iodine to highlight different parts of the tissue. The solution was visible in muscular parts of the heart, and to a lesser degree in portions of the heart associated with conducting, giving investigators high resolution 3-D images of the conducting tissue.

They were able to fully identify the network that produces electrical activity and controls heart rhythm.

Numerous heart structures could be identified with the technology including the sinoatrial node and the atrioventricular conduction axis: the penetrating bundle, His bundle, the bundle branches and the Purkinje network.

The images are the first three dimensional representations of the cardiac conduction system within a single intact mammalian heart. The images could aid clinicians in finding ways to reduce fibrillation, which occurs when the heart muscle contracts chaotically and fails to pump blood rhythmically around the body.

"Computer models based on these high-fidelity images will help us to understand why the heart rhythm is vulnerable to changes in heart size, blood supply, or scarring after a heart attack," Jarvis said.

"One of the major concerns for surgeons in repairing malformed hearts, for example, is to avoid damage to the tissue that distributes electrical waves."

"If they had access to 3-D images of the conducting tissues in malformed hearts, however, it could be possible to understand where the conducting tissue is likely to be before they operate."

The research was recently published in journal PLoS One.

Review Date: 
April 26, 2012